SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '94c9a56350cbc4167595bd65126326457c224576f003f4acc271a6054979bfae' 
  AND token = '/kcrm2WkZ0wlaBMec/4X3rPEcu+LyqQh0My6Hr9Hx80=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}